Short answer: you need a cybersecurity consultant when the cost of one breach would hurt more than the cost of an assessment — and nobody on your team owns security full-time. For most startups that point arrives somewhere between your first enterprise customer and your Series A.
Here are the seven signals I see most often.
1. A customer or investor asked for a penetration test report
This is the most common trigger. Enterprise procurement, SOC 2 auditors, banking partners and insurers all ask for third-party evidence. Your own team cannot produce that evidence — the whole point is independence. If a deal is blocked on a security questionnaire, you already need a consultant.
2. Nobody on your team owns security
Engineers ship features. DevOps keeps things running. Security becomes "everyone's job", which means it is nobody's job. A consultant gives you a named owner for a defined window, plus a prioritised backlog your engineers can actually work through.
3. You handle money, health data, or identity
Fintech, healthtech and anything touching KYC/identity data are targets by default. Attackers do not care that you are small — automated scanners do not check your headcount. If a breach would trigger regulatory reporting (NDPR, GDPR, HIPAA, PCI DSS), get an external assessment before regulators force one.
4. You just shipped something big
New payments flow, new public API, new mobile app, a migration to a new cloud account. Big changes are where logic flaws live: broken access control, IDOR, insecure direct object references in a new endpoint. Automated scanners miss these almost every time because they require understanding your business logic.
5. Your scanner output is a wall of noise
Vulnerability scanners produce hundreds of findings ranked by CVSS, not by what an attacker would actually exploit in your environment. A consultant's job is triage: which three of these 240 findings would actually let someone into your database, and what is the fix.
6. You cannot answer "what would an attacker do first?"
If your team cannot describe, in one paragraph, the most likely path from the public internet to your most valuable data, you do not have a threat model. That paragraph is the deliverable of a good consulting engagement.
7. Something already happened
Suspicious logins, an unexplained data export, a leaked API key on GitHub, a ransom email. Do not investigate alone if you might need the evidence later. Bring someone in early.
What a consultant actually does
A real engagement is not "run a scan and send a PDF". It looks like this:
Scoping — agree what is in scope (domains, APIs, mobile builds, network ranges), what is off-limits, and what "done" means.
Reconnaissance and threat modelling — map your real attack surface, including the subdomains and staging boxes you forgot about.
Manual testing — authentication, session handling, access control between roles and tenants, business logic, injection, file handling, cloud misconfiguration.
Exploitation and impact proof — not "this parameter is reflected" but "here is the screenshot of another customer's data".
Reporting — findings ranked by real business impact, with reproduction steps your engineers can follow and specific remediation guidance.
Retest — verify the fixes actually closed the hole.
When you do NOT need a consultant yet
Be honest with yourself. If you have no production system, no customer data, and no compliance pressure, spend your money on the basics first: enforce MFA everywhere, turn on dependency scanning, remove secrets from your repo, enable logging and backups, and use least-privilege cloud roles. A consultant will just tell you to do those things and charge you for the privilege.
How to get started without wasting money
Start with a scoped, time-boxed assessment on your highest-risk asset — usually the main web application plus its API. One or two weeks of focused manual testing on your crown jewels beats a shallow scan of everything. Then use the report to build a 90-day remediation plan, and retest.
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Need a second opinion on your security posture?
I'm Michael Adeyanju, a penetration tester and security consultant working with companies globally — web app, API, mobile and network security. Based in Lagos, Nigeria, available for remote and on-site engagements worldwide.
Book a 15-minute call: cal.com/michaeladeyanju/15min
See what an engagement covers: michaeladeyanju.com/security-engineer